Interesting to see ESRI’s perspective:
“While they are quite different, and designed for different applications, one cannot help but compare them. In the last five years, the world has made a distinction between traditional GIS and web mapping. Traditional GIS has been focused on the enterprise applications and been the domain of GIS professionals, whereas web mapping has been pervasive with global content and easy to use viewers. With the release of 10.1 and the integration of ArcGIS Online, Esri has introduced a whole new platform that integrates traditional GIS with a cloud platform, has rich global data that is simple and easy-to-use, and a new generation of web and device apps that enable the same consumer experience of web maps common on the Internet today. Beyond this, however, ArcGIS 10.1 provides the full power of traditional GIS with data management, spatial analysis, and visualization only available in GIS. It also supports the ability to seamlessly integrate workflows based on traditional technology with a server or the cloud environment allowing for automatic conversion of geospatial data into web services accessible by any web or device app. These services can be easily viewed and queried and can incorporate spatial analysis. They can also be mashed up with consumer maps and web services, embedded in websites, blogs and emails and can also be marked up (e.g., via redlining and sketching). These maps can be shared dynamically and used by everyone through a browser, mobile device, in a desktop GIS system, or in a custom application.
The new generation of ArcGIS offers many opportunities for GIS professionals and GIS organizations. It introduces the ability to easily disseminate high-quality maps and provide services for virtually anyone to use and integrate into their activities. This will result in more dissemination and accessibility of geographic knowledge and realizes the GIS vision of multi-disciplinary integration.”